Chain wear

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Brucey
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Re: Chain wear

Postby Brucey » 16 Jan 2012, 1:35pm

conditions of use and maintenance vary wildly though. At one extreme I have a nice road bike which only sees use on dry days. At the other I have MTBs which run in 'dilute mud' if they are lucky.

Needless to say the maintenance is not the same for each! What I have found is that given enough care and cleaning, even the MTB chain/block will outlast a casually maintained roadbike or commuter bike chain/block.

There is no one-size-fits-all 'perfect solution', (even the kind of mud and dirt that winds up on the chain makes a difference, and this varies greatly with region...) -thus you have to make your own appropriate choices on this one, preferably guided by experience, personal or otherwise.

cheers
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Graham
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Re: Chain wear

Postby Graham » 11 Feb 2015, 5:06pm

February 2015 - The winter conditions have just killed my chain.

A KMC Z8S ( 8-speed ) has just given me 854 miles before grounding out on a Rohloff Caliber 0.075mm gauge.

Only grounding out in a few places, but not so far off on many others.

Have I really become so lazy about chain-cleaning ?? This is a wake-up call.

[ I choose to unzombify this topic because there are some interesting comments from CJ & Brucey up-thread ( some of which relate to the Rohloff Caliber ).
Reading for later. ]

EDIT : The crucial thing to realise is that the Rohloff Caliber effectively measures two sets of bearing wear - by pushing the rollers apart in opposite directions.
The CJ fix is to jam one of the (measured) rollers in a fixed position towards the other one so that this distorting error is reduced / eliminated.

Thanks CJ :D

I best be hauling that formerly-known-as-a-dead-chain out of the dustbin . . . and unzombify that too !!
Last edited by Graham on 11 Feb 2015, 9:06pm, edited 2 times in total.
Reason: Update : CJ measuring tool correction restated. Corrected chain model KMC Z8S

Thomas125
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Location: Telford, West Midlands

Re: Chain wear

Postby Thomas125 » 11 Feb 2015, 7:33pm

Does the 1/8" stretch still apply if you're running a hub gear?
Was 93.4kg now 78.3kg

Next target 74.0kg

"Life is one long bike ride" :-)

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NATURAL ANKLING
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Location: English Riviera

Re: Chain wear

Postby NATURAL ANKLING » 11 Feb 2015, 7:58pm

Hi,
My target this year is 75 kgs :)
Back on subject, I am not impressed with KMC chains at all I managed to demolish to breaking a bog standard 7 speed fitted to a cheap bike, whatever the cheapest KMC chain (derailleur type) in just 300 miles :?
And it was past 1 %.
Priority Is Still 500K In 24..Just Dreaming...Stay Focused Guys And Keep Sharp...
You'll Find Me At The Top Of a Hill...............Somewhere

Thomas125
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Location: Telford, West Midlands

Re: Chain wear

Postby Thomas125 » 11 Feb 2015, 9:01pm

I got 500 miles from a Yapan S8 chain on an Alfine hub bike, before it snapped.

I too need to pay more attention to chain maintenance.

I just bought a KMC Z8 to replace it so I'm hoping mined is ok :!:
Was 93.4kg now 78.3kg

Next target 74.0kg

"Life is one long bike ride" :-)

Brucey
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Joined: 4 Jan 2012, 6:25pm

Re: Chain wear

Postby Brucey » 11 Feb 2015, 9:09pm

Thomas125 wrote:Does the 1/8" stretch still apply if you're running a hub gear?


If you want the sprocket and the chainring to last more than one chain, it is wise to use the 1/8" (1%) rule even on IGH chain.

But.... I quite often run them out to 2% and it seems OK provided you leave enough chain slack to allow the chain to reach the position it wants to assume, which is 2% further outwards than normal; if you tension the chain fully, it can't do that.

BTW fancy Alfine sprockets have plastic guards and other such flim-flam but SA sprockets will also fit on the hub and these are very durable (in 1/8" form) and cost peanuts. So when the 3/32" sprocket wear out, I'd suggest that you get a 1/8" one instead, and to use a full roller 1/8" chain like a KMC Z1.

cheers
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~~~~~~~~~~~~~~~~~~~~~~Brucey~~~~~~~~~~~~~~~~~~~~~~~~

JohnW
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Location: Yorkshire

Re: Chain wear

Postby JohnW » 11 Feb 2015, 9:29pm

KMC Z82 - ? - I've looked through my Madison catalogue, and on the KMC website, and I can't find that one. It's all very bewildering because the KMC web-site and the KMC pages in the Madison catalogue differ quite a bit, and it's difficult to be sure which is which - it doesn't help when the catalogue pictures quote different reference numbers.

However, I've found that KMC chains give me the best service. I ride derailleur systems exclusively, triple chainsets, 8, 6 and 5 speed blocks depending upon which bike, and the most recent to be worn-out and removed was (I think) a Z8S - which is a bog standard chain with black inner-link plates and plated outer-link plates - this is also quoted as 'K51 in the Madison catalogue.

My own experience with KMC chains leads me to the opinion that they are very satisfactory indeed, and I don't have a problem. I've been using KMC chains for at least a dozen years, and generally I get through two a year. I get from 7,000 miles on a bike which is off the road through winter to between 4,000 and 5,000 miles from a bike which rides through winter. We do get winters up here in the north and, however much I try to avoid it, I ride through snow, salt, crud..............and all the rest. I don't ride off-road (except towpaths and less than perfect so-called cyclepaths) and I do attend to lubrication.

Graham's report of 854 miles is quite disturbing, and perhaps there's an explanation.

I never measure the wear/stretch in a chain. I called at a bike shop some miles from home on one occasion and the proprietor insisted (as a service to customers) on coming out and giving my chain a check. He put his gadget on and there was a sharp intake of breath..........followed by "that's overdue for a change sir............" (or words to that effect). I think I had perhaps 2,000 miles on the chain by that time.I didn't listen and I rode on for three of four months and got the usual miles from the chain.

I change my chains when I consider them worn out. I can feel it through the pedals when it's worn in. On work bikes, I've ridden for weeks on chains with several rollers missing - in winter, when it'd be a waste to put a new block and chain on.

I've taken the cassette and chain off my 'best' bike over the winter to give myself a lower bottom (gear that is, it's not an anatomical rearrangement :lol: :lol: :lol: :lol: ) and saved the cassette and chain for reuse on a winter bike. They've done over 6,100 miles and there's a bit of life left in them.

854 miles Graham - there's surely something wrong there..............or is it on an MTB that you use for playing out in the mud in a sandy district!

EDIT by Graham : I'm doing this to keep the info in one place.
Thanks for your comments John.
Yes, your are right - it was a KMC Z8S . . . I have corrected it in my post above.
I admit to being a bit more lax with my chain-cleaning this winter due to disruption to my "chain-cleaning infrastructure" :shock:
However, this is possibly an extra 50-miles after each time I noticed that the chain definitely did need cleaning.
Anyhow, I will experiment with "worn-out" one in the light of the comments by CJ about the Rohloff Caliber chain-wear measurer and report back.

Brucey
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Re: Chain wear

Postby Brucey » 11 Feb 2015, 9:55pm

John W is clearly using the 'one chain, one cassette, run it to the finish' method. This is OK but it can see the chainrings off a fair bit quicker than normal.

The idea of using a chain wear gauge is that you have a chance to fit a new chain before the cassette is so worn that it won't take a new chain without jumping. This is usually about 1/3rd as much wear as you would find in a 'completely cream-crackered' cassette and chain.

It is quite debatable as to which method is most cost-effective. Whilst cassettes are expensive and chains are cheap, the latter has something going for it, but when good chains are pricey and OK cassettes are pretty cheap, maybe John's scheme is OK provided the chainrings don't die too soon.

Maybe the best scheme of all is to rotate chains to 0.75% and then rotate them again, to 1.-something percent, and so on. It is a lot of faff though.

cheers
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~~~~~~~~~~~~~~~~~~~~~~Brucey~~~~~~~~~~~~~~~~~~~~~~~~

JohnW
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Re: Chain wear

Postby JohnW » 11 Feb 2015, 10:03pm

Brucey wrote:John W is clearly using the 'one chain, one cassette, run it to the finish' method. This is OK but it can see the chainrings off a fair bit quicker than normal.

The idea of using a chain wear gauge is that you have a chance to fit a new chain before the cassette is so worn that it won't take a new chain without jumping. This is usually about 1/3rd as much wear as you would find in a 'completely cream-crackered' cassette and chain.

It is quite debatable as to which method is most cost-effective. Whilst cassettes are expensive and chains are cheap, the latter has something going for it, but when good chains are pricey and OK cassettes are pretty cheap, maybe John's scheme is OK provided the chainrings don't die too soon.

Maybe the best scheme of all is to rotate chains to 0.75% and then rotate them again, to 1.-something percent, and so on. It is a lot of faff though.

cheers


Brucey - I've tried all sorts of sophisticated ways of making chains/blocks/cassettes last longer, and I've found that my routine is the least costly in the long run (and the least bother). I turn my chainrings a fifth of a turn every time I change chains, and I get three to four block/chain ensembles to each middle and inner chainring.............as the decades go by, I change big rings with decreasing frequency! That may change, because I've just bought a 26/36/46 chainset!

Thomas125
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Location: Telford, West Midlands

Re: Chain wear

Postby Thomas125 » 11 Feb 2015, 10:11pm

Npt sure why you couldnt find it John.

it's thia one I've gone for:

http://www.chainreactioncyclesis%20defimitely%20welcomcom/mobile/kmc-z8rb-anti-rust-8-speed-chain/rp-prod120638

Thanks for the tip Brucey. I think I'll definitely go down that route for next winter.

My bike is my sole means of transport so its out every day in all weathers. Anything thats more robust is very welcome.

Thomas
Was 93.4kg now 78.3kg

Next target 74.0kg

"Life is one long bike ride" :-)

Brucey
Posts: 31933
Joined: 4 Jan 2012, 6:25pm

Re: Chain wear

Postby Brucey » 11 Feb 2015, 10:28pm

John, It'd be interesting to know what % stretch your chains are at when they are 'worn out'.

I've seen some ridiculously worn chainrings but only when the chain is really stretched.

Provided the chain will sit out on the chainring teeth where it should do (and doesn't move under load) then a worn chain isn't a disaster on a chainring; for every 1% a chain is stretched on a 50T chainring, the chain will sit ~1mm further out. Arguably if you only use chains to 1% then chainrings become hooked, whereas if you run them out to 4% then the teeth might even be more evenly worn... :wink:

I think when everything is new the chain rollers sit nicely on the teeth and the rate of wear is low. But once the chain starts to stretch, the chain rollers sit against a flat (not curved) part of the tooth and if the chainring material is not hard, and the loads are high (eg riding out of the saddle up every climb) then the chainrings wear at an accelerated rate. If the wear rate of the chainring is high enough then the chainring can become hooked and if it is bad enough the chain will sit in the hooks even when it is more worn (bad). But if the chain continues to stretch quickly and the loads are low, the chainring teeth may not become hooked and the tooth profile may be reasonably well preserved.

cheers
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~~~~~~~~~~~~~~~~~~~~~~Brucey~~~~~~~~~~~~~~~~~~~~~~~~

JohnW
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Location: Yorkshire

Re: Chain wear

Postby JohnW » 11 Feb 2015, 10:38pm

Thomas125 wrote:Npt sure why you couldnt find it John.

it's thia one I've gone for:

http://www.chainreactioncyclesis%20defimitely%20welcomcom/mobile/kmc-z8rb-anti-rust-8-speed-chain/rp-prod120638

Thanks for the tip Brucey. I think I'll definitely go down that route for next winter.

My bike is my sole means of transport so its out every day in all weathers. Anything thats more robust is very welcome.

Thomas

Thomas - you've spelt "definitely" wrong - you've typed "defimitely".........the link doesn't work. Don't worry - it's just the kind of thing that I do.

Thomas125
Posts: 411
Joined: 23 Sep 2008, 6:50pm
Location: Telford, West Midlands

Re: Chain wear

Postby Thomas125 » 11 Feb 2015, 10:46pm

Laptop batteries gone Im on the phone :roll:

http://www.chainreactioncycles.com/mobile/kmc-z8rb-anti-rust-8-speed-chain/rp-prod120638

Lets hope this works :!:
Was 93.4kg now 78.3kg

Next target 74.0kg

"Life is one long bike ride" :-)

JohnW
Posts: 5937
Joined: 6 Jan 2007, 9:12pm
Location: Yorkshire

Re: Chain wear

Postby JohnW » 11 Feb 2015, 11:00pm

Thomas125 wrote:Laptop batteries gone Im on the phone :roll:

http://www.chainreactioncycles.com/mobile/kmc-z8rb-anti-rust-8-speed-chain/rp-prod120638

Lets hope this works :!:


Thanks Thomas - got it. :D :D :D

wearwell
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Re: Chain wear

Postby wearwell » 10 Mar 2015, 8:14am

Just noticed this thread. I may be repeating something but my theory of maximising chain life is to never clean it.
Oil it frequently but allow the black road dust to accumulate - it gets ground very fine - if you remove it it just gets replaced it with fresh sharp grit which will wear much faster. The old dust fills voids and "fairs in" spaces, giving protection from fresh grit by allowing it no place to lodge. It's a bit mucky if you need to handle a chain though.
I replace chains (and /or blocks, chain rings) when they start to fail i.e. slip over the teeth. You have to look closely to see which bits need replacing and perhaps even measure the chain to see how far it's gone.
Once my chain ring teeth were worn so thin that they started getting stuck in the gap between the worn rollers and the links. Quite pleasing to get everything wearing out in sync; you know you have got your moneys worth and you can start again with everything nice and new!